Cerastes

Cerastes was a monster from Greek legend with the body of a snake and horns like a bull or ram. According to legend, the monster would bury itself in the sand except for its horns, which protruded from the ground. Other creatures would approach the mysterious horns to see if a carcass was nearby, whereupon the Cerastes would emerge from the earth and devour the victim. Although the creature sounds fanciful to the point of absurdity, it found a home in many medieval bestiaries, and no less a person than Leonardo da Vinci wrote about it.

The Horned Desert Viper

The legend however, does have a kernel of truth. The North African horned desert viper has small horn-like appendages above its eyes and it hides in sand to stalk its prey (plus the snake already blends in with the desert due to camouflage coloration). The desert viper only measures 60 centimeters (about a foot) in length, so it is hardly swallowing large beasts like the mythical cerastes! Yet the desert viper is also acutely toxic—not to mention, real– and a mere 40 ml of venom are enough to kill a person. Fortunately the desert viper is a good-tempered snake and tends to warn victims before striking by rubbing its scaly coils together to make a hissing/sawing noise. The resemblance was enough however that taxonomists gave the little viper the scientific name Cerastes cerastes.